To support their argument, the anti-zoo advocates often point to a 2008 study in the journal Science, which found that captive African elephants live far shorter lives than their counterparts in a Kenyan national park—a median of 16.9 years in zoos versus 56 years in the park.
So what's the bottom line? First, you shouldn't support a non-accredited zoo unless you have independently investigated its animal-care standards, a task few people can accomplish on a Saturday morning. Second, even if you're at a good zoo, keep your eyes and ears open for signs of distress and don't be afraid to ask the docents about what you're seeing; better zoos will keep their people informed and capable of providing honest answers. Finally, if you can't stand the sight of an animal staring longingly through a glass pane, you probably should just stay home.
The Lantern thanks Chris Draper of the Born Free Foundation, Steve Feldman of the AZA, and Dr. Don Moore of the National Zoo.